Background: The purpose of this study was to determine the causes and the prognosis of consecutive patients resuscitated from cardiac arrest occurring in a general hospital. We assessed 28 females and 94 males (aged 13-82 years) who were resuscitated from cardiac arrest not attributable to acute myocardial infarction. Ventricular fibrillation (VF) was documented in 97. Non-cardiac causes were excluded. Non-invasive studies (24 h Holter monitoring, 2D echocardiogram, signal-averaged ECG, exercise testing, magnetic resonance imaging) and invasive studies (right and left ventricular angiography, coronary angiography and complete electrophysiologic study (EPS) were performed.
Results: An underlying cardiac disease was found in 107 patients (88%). Patients were followed for a period ranging from 6 months to 10 years (mean 4+/-5 years). Several causes for cardiac arrest were identified and treated specifically. The prognosis was variable. Among surviving patients the following causes of cardiac arrest were found: Wolff-Parkinson-White syndrome (n=2), rapid supraventricular tachycardia (n=6), acquired or congenital long QT syndrome (n=7), complete atrioventricular block (n=3), proarrhythmic effect of an antiarrhythmic drug (n=5), vasospastic angina (normal coronary arteries) (n=5). Among ten patients with VF related to cardiac ischaemia two died suddenly. Ventricular tachycardia (VT) or VF was the main cause leading to resuscitation after cardiac arrest (n=64). The risk of recurrence of arrest is confirmed in the present study particularly in patients in whom VT/VF could not be suppressed by antiarrhythmic drug therapy (n=45) and in those where an ICD was not implanted (18 cardiac deaths (nine sudden cardiac deaths (SCD's)). The cause of cardiac arrest was not elucidated in 20 patients (16%). The prognosis of these patients differed according to the documentation of VF at the time of cardiac arrest: of those with documented VF (n=12), six patients died suddenly (one with an ICD); of those without documented VF (n=8), all are alive.
Conclusion: To determine the precise cause of cardiac arrest was the first problem; the diagnosis of cardiac arrest clearly was erroneous in 8 of 122 patients (6.5%). In other patients, a ventricular tachyarrhythmia was identified as the cause for cardiac arrest in half of the population; the indication for an ICD is evident in this group. In 31% of patients with proven cardiac arrest, another arrhythmia requiring specific treatment was identified and ICD implantation was avoided; these patients had a survival of 92% at 3 years. In patients without an identified cause of cardiac arrest and negative EPS, the prognosis was unfavorable only in those with documented VF.